Molecular Basis for gamma/delta T Lineage Specification

描述（由申请人提供）：在胸腺发育过程中，祖细胞对γδ谱系的承诺和它们的效应命运的规范都发生了；然而，我们对控制这些命运决定的发育线索的理解仍然不完整。越来越多的证据表明，γδ谱系承诺和效应者命运都受到T细胞受体（TCR）信号强度差异的影响。TCR信号强度的差异通过诱导E蛋白DNA结合拮抗剂Id3影响命运。虽然E蛋白明显发挥着核心作用，但它们对发育结果的影响几乎肯定是由其他转录因子和控制其表达和功能的细胞外信号调节的。因此，这些命运决定太过复杂，无法通过专注于一个基因或途径来理解，因此需要Murre开创的基于网络的综合方法。该计划的总体目标是确定不同强度的γδ TCR信号是如何产生的，并了解E蛋白活性和协同dna结合蛋白的最终改变在影响谱系和γδ效应物命运中的作用。全面了解这样一个多方面的发育过程超出了任何一个实验室的能力范围，因为它需要大量的实验方法来操纵决定命运的线索，并评估它们对命运的影响，无论是在功能上还是在分子上，在体外还是体内。组成该计划的调查人员拥有必要的独特而又互补的技能来做到这一点。Wiest实验室（项目1）已经建立了体内和体外模型，其中可以通过改变TCR信号强度来操纵发育命运。Zuniga-Pflucker博士（项目3）建立了优雅的体外和体内系统，其中Notch和细胞因子输入可以被操纵以评估对效应器命运的影响。Drs。庄（项目2）和Murre（项目4）是E蛋白及其Id家族拮抗剂的遗传和分子分析专家。最后，Murre博士（Genomics Core）将利用他新颖的生物信息学方法，通过组装围绕E蛋白靶点组装的全球调控网络，协助所有项目在分子定义γδ发展的关键里程碑。总的来说，这些努力有望通过全面定义从细胞外信号到细胞核靶标网络控制γδ谱系承诺和效应物命运的过程，推动该领域向前发展。

DESCRIPTION (provided by applicant): Both the commitment of progenitors to the γδ lineage and specification of their effector fates occurs during development in the thymus; however, our understanding of the developmental cues controlling these fate decisions remains incomplete. Accumulating evidence suggests that both γδ lineage commitment and effector fate are influenced by differences in T cell receptor (TCR) signal strength. The differences in TCR signal strength influence fate by inducing Id3, an antagonist of E protein DNA binding. While E proteins clearly play a central role, their influence on developmental outcomes is almost certainly modulated by additional transcription factors and the extracellular signals that control their expression and function. Accordingly, these fate decisions are too complex to be understood by focusing on one gene or pathway and so require the comprehensive, network-based approach pioneered by Murre. The overall goal of this program is to determine how γδ TCR signals of varying intensities are generated and understand the role that the resultant alterations in E protein activity and cooperating DNA-binding proteins play in influencing lineage and γδ effector fate. Gaining a comprehensive understanding of such a multifaceted developmental process is beyond the scope of any individual laboratory, as it requires facility with numerous experimental approaches to manipulate fate-determining cues and assess their effect on fate, both functionally and molecularly, in vitro and in vivo. The investigators comprising this program possess the necessary distinct, yet complementary, skills to do so. The Wiest lab (Project 1) has generated in vivo and in vitro models in which developmental fates can be manipulated by altering TCR signal intensity. Dr. Zuniga-Pflucker (Project 3) has established elegant in vitro and in vivo systems in which Notch and cytokine input can be manipulated to assess the impact on effector fate. Drs. Zhuang (Project 2) and Murre (Project 4) are experts in the genetic and molecular analysis of E proteins and their Id family antagonists. Finally, Dr. Murre (Genomics Core) will utilize his novel bioinformatic approach to assist all projects in molecularly defining critical milestones in γδ development by assembling global regulatory networks assembled around E protein targets. Collectively, these efforts promise to move the field forward by comprehensively defining the processes controlling γδ lineage commitment and effector fate from extracellular signals to the network of targets in the nucleus.